fix: stabilize relayHints in useProfile to prevent fetch abort loop

relayHints was used directly in the useEffect dependency array, so
callers passing a new array literal (e.g. [p.relay]) on every render
caused the effect to re-run each cycle — aborting the previous network
fetch before it could complete. The IndexedDB fast-path masked this in
the feed view (profiles already cached), but the detail view showed
raw pubkeys because profiles were never fetched from the network.

Wrap relayHints in a JSON.stringify-based useMemo (same pattern as
useStableArray) so the effect only re-runs when the actual relay
values change.

https://claude.ai/code/session_01XjwLaShFSVPR5gNA7iUjuB

src/hooks/useProfile.ts

@@ -1,4 +1,4 @@
-import { useState, useEffect, useRef } from "react";
+import { useState, useEffect, useRef, useMemo } from "react";
 import { profileLoader } from "@/services/loaders";
 import { ProfileContent, getProfileContent } from "applesauce-core/helpers";
 import { kinds } from "nostr-tools";
@@ -22,6 +22,14 @@ export function useProfile(
   const [profile, setProfile] = useState<ProfileContent | undefined>();
   const abortControllerRef = useRef<AbortController | null>(null);
 
+  // Stabilize relayHints so callers can pass [p.relay] without causing
+  // the effect to re-run (and abort in-flight fetches) every render.
+  const stableRelayHints = useMemo(
+    () => relayHints,
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+    [JSON.stringify(relayHints)],
+  );
+
   useEffect(() => {
     if (!pubkey) {
       setProfile(undefined);
@@ -45,7 +53,8 @@ export function useProfile(
     const sub = profileLoader({
       kind: kinds.Metadata,
       pubkey,
-      ...(relayHints && relayHints.length > 0 && { relays: relayHints }),
+      ...(stableRelayHints &&
+        stableRelayHints.length > 0 && { relays: stableRelayHints }),
     }).subscribe({
       next: async (fetchedEvent) => {
         if (controller.signal.aborted) return;
@@ -85,7 +94,7 @@ export function useProfile(
       controller.abort();
       sub.unsubscribe();
     };
-  }, [pubkey, relayHints]);
+  }, [pubkey, stableRelayHints]);
 
   return profile;
 }